Valve for water meters



April 9, 1940. E. NUEBLING 2,196,425

VALVE Fon WATER METERS v original Filed March 22, 1935 4'Sheets-Sheefc 24 I N V EN TOR. l* 1S -on//Mo /VUEBL N6 A TTORNE YS.

4 Sheets-Sheet 3 NVENTOR.

Eo :Mq/a9 Nuss/ v6 8% MMM/aq( E. NUEBLING VALVE FOR WATER METERSOriginal Filed March 22, 1935 April 9, y1940.

ATTORNEYS.

Y April 9, 1940.. E. NU'EBLING VALVE FR WATER METERS Oiginal Filed March22,' 1935 4 Sheets-Sheet 4 fffffff n.

INVENTOR. 0554 /NG y A TTORNEYS.

Patented Apr. 9, 1940 UNITED STATES PATENT OFFICE claims. (o1. 277-20)The invention relates lto water meters and more particularly to thatrtype thereof commonly referred to as fire-service vmeters adapted to'`measure the quantity of water supplied to sprinklers and other systemsintended to Abe used for the extinguishing 'of res; Although water mayrarely be required for the purpose of extinguishving fires, experiencenevertheless has demon- 1, strated that if a lire-service supply is notmetered,

leakage and improper use, with few exceptions, result in large andmaterial losses.

In order that all ilows likely to pass through a meter of the indicatedtype may be properly measured, it is essential that the meter operateaccurately over a wide range in the rates of flow. Furthermore, whenduring fire emergencies or for other reasons the lire-service system isrequired to deliver large quantities of water for fire iighting or otherpurposes, it is 'essential that the meter permit va free and maximum owof water through it Without obstruction and without appreciable loss ofpressure head. f

The principal object of the present invention is to provide a novel andimproved meter of the,

indicated class which will function with maximum accuracy at all ratesof oW through the meter.4

capable of being sold at relatively low cost and ofv withstanding longperiods of service Withoutkfrequent attention, adjustments or repairs. c

`Other more specific objects Will appear from the descriptionhereinafter and the features of Anovelty f will be pointed out in theclaims.

The instant application is a division of another application led by mein the United States Patent Oflice on March 22, 1935, Serial No. 12,372

nowPatent No. 2,099,139, patented November 16, 1937. Y

In the accompanying drawings whichillustrate examples of the invention,Without dening its limits, Fig. l is a sectional elevation of oney formof the novel meter; Fig. 2 is a plan View thereof with parts in section;Fig. 3 is a cross section on the line 3--3 of Fig. l; Fig. 4 is afragmentary cross section on the line 4-4 of Fig. 1; Fig. 5

i is a fragmentary sectional View on the line 5-1-5 of `Fig. 2; Fig. 6is a detail sectional elevation on an enlarged scale showing themeasuring ap-- i of ilow through the novel meter.

As shown in Fig. 1 of the drawings, the meter includes casing preferablyconsisting of an inlet section l5 provided with a anged inlet I6 adaptedfor connection with a conduit leadingto a` source of supply, and anoutlet section vl'i terminating in a hanged outlet I8 arranged to beconnected with an outlet pipe in which a control valve may be located inthe customary manner; the casing sections l5 and Il are connected witheach other at their opposed4 flanged ends in any convenient manner as bymeans `of bolts vor the like I8. The sections l5 and Iltare preferablyof cylindrical shape and 'of dimensions suitable to 'the purpose forwhich they are designed. The

inlet section I5 is provided withan internal -partition 20 having anaperture in which the one end section ,l5 withv the outlet lchamber Ilaof the section Il." The throat-piece as shown is provided with aninternal axial passage 2Ia and with bypass channels 22 which preferablyare llocated e`xteriorly about said passage 2 la and establishcommunicationbetween a passage 23 formed by the partition 26 in thesection l5 and the outlet chamber lle of thesection l1, as illustratedl.The throat-piece 2l further includes an outwardly directed passage 23athe purpose of which will appear lmore fully hereinaftenand has itsright hand end in Fig. 1 formed with a preferably rounded or `curved'valve .seat 24 located in the f outlet chamber ila of the section l1.

A n annular member rprovided with slots 26 is accurately fitted into theupwardly .projecting portion 15b of the section I5 and rests upon anannular shoulder l5 formed thereinj the annular member 25 is fixed inplace in any convenient 'manner' as for instance by means of an uppercasing member 2l whichitself is secured in position'by means of bolts orthe like 28. The slot-ted annular member 25 serves as a screen and asupvport for the measuring chamber 29 which contains the measuringpiston 3i in the formshown in the drawings the latter is of thewell-known nutating disc type, it being understood, however,

Ithat this typeof piston 3d may be replaced vby' any other equivalentmeans for effecting the ,desired measuring results. The annular slottedmember 25 is further provided with an outlet port 3| which leads to thepassage 23 and is provided at its exit' end with an vorali-loe plate 32provided with an opening 33 of predetermined size and held in place torinstanceby means of a collar 34, as

l shown in Fig. 1, said collar 34 being screwed into nally with anenclosed chamber 31 in which ismounteda reduction'gearing 38 which isarranged to be operated bythe measuring piston 30 shown in Fig. l, andwhich drives a shaft 39 extending vertically through a suitable stuffingbox.y 40 externally of the meter and into operative connection with themeasuring or totalizing means as illustrated in Fig. 6 whereby the iiowspassing through the meter are properly measured. In the illustratedexample, as shown best in Fig. 6, the shaft 3S is provided with aattened reduced end Il! which engages a driving pin 42 mounted in theprojecting end or shaft 43 of a friction disc 45. The disc 44 isrotatably mounted preferably on ball bearings G5 and its shaft 13 isarranged to rotate in a bushing i5 which is preferably made ofself-lubricating material, such as metalized graphite, and is fitted inan upright bearing 4l mounted within a casing 48 which itself is `fixedin place upon the upper casing member E?, for instance, by means ofsuitable screws t9 or their equivalent.

The friction disc 44' isarranged to drive two. friction wheels 5G and 5|mounted respectively upon shafts 52 and 53, the latter being rotatablymounted preferably by means of conical pivotbearings in posts dependingfrom the bottom plates of registers of totalizers 54 and 55respectively. The shafts 52 and 53 are connected by suitable bevel gears56 and 5'! with the actuating mechanisms of the totalizers 54 and 55which operate in any customaryv and welhknown mauner. The totalizers 54and 55 including the shafts 52 and 53 are free to pivot vertically asindependent units about conical pivot bearings 582u and 58 respectively,said pivot bearings 58a and 53 being fixed on carriages 59 and 60slidably mounted in horizontal directions onparallel guide rods 6|supported by` brackets 52 mounted upon the casing 45 as illustratedinFig. 6. Leaf springs 53 fixed upon members B4 and 65 of the carriages 59and 60 respectively, bear against the totalizer units 54 and 55 and tendto pivotally actuate such totalizer units about the bearings 58 and 58in directions to press the friction wheels 5S and 5| into engagementwith the upper surface of the friction disc 114 with just suicient forceto keep said friction wheels 50 and 5| at all times in proper operativeengagementfwith the disc Ml. To protect the totalizing means andassociated elements, a suitable cover BS is removably fixed upon theeasing 48 in any convenient manner for instance by means of suitablescrews, said cover 56 being providedwith sight openings closed by glassor other transparent sections 6T in Vertical registrywith the totalizers55. and 55.

With the arrangement illustrated and described, it is obvious that anymovement of the meter piston 3G will be transmitted through the systemsof gears and co-operating parts to the totalizers 54 and 55. Inoperation the meter piston 313 displaces or carries over a xed quantityof liquid during each revolution, which move-- ments of the piston 30are translated bythe aforesaid systems of gearing and cci-operatingelements into convenient units of measurement indicated by thetotalizing means or mechanism such as cubic feet or gallons. Thetotalizing means or mechanism will indicate a true measurement of flowonly when the meter has been properly calibrated by suitable gearadjustment.

ecause of tolerance allowed invmachinery, no two meters are exactlyalike and the aforesaidadjustment is based onl an actual test made bypassing a quantity of water through the meter, which quantity ismeasured either by discharging into a tank of known capacity or byWeighing the amount of water discharged. In the instant construction,the required adjustment either to calibrate the meter or to alter thereadings of the totalizing means or mechanism may be readily effected-byshifting the friction wheel 50 across the face of the disc 44. This maybe accomplished by sliding the carriage 59 toward 0r away from. thecenter of the disc 44 and then fixing said carriage 59 in its adjustedposition in any convenient manner. The purpose of the two totalizers 54and 55 andtheir associated elements will be more clearly set forthhereinafter.

The meter further includes the novel duplex valve illustrated in thedrawings and shown in detail in Fig. l, which duplex valve overcomesobjections found in hydraulic valves as heretofore constructed for thepurpose of offering a definite resistance to the initial opening of thevalve under liquidpressure anda reduced or negligible rcsistance` oncethe valve has started to open.

The duplex valve under discussion in its illustrated form consists of avertical flap member 68 and a co-operating horizontal fia'p member 69both pivotally mounted at right angles to each other upon a carrier 'l0which, if necessary or desired, may include a weight '1| The carrier 1Dis mounted upon a support 'l2 hinged upon ahorizontal rod 13 suitablyfastened in a bearing bracket 'I4 secured to the throat-piece 2|, forinstance, by means of bolts or the like l5. The flap member 68 isadapted to engage the preferably rounded seat 21|' of the throat-piece2| while the fiap member 69 is arranged to engage a correspondinglyrounded seat 'I6 for the purpose ol controlling the iiow through theaxial passage 2H which with the inlet chamber I5n and outlet chamber Il@constitutes the main line channel of the meter, the passage 2 |1-representing a constricted portion of such main line channel. The seat'It constitutes part of a valve ring 'l1 which is adjustably threadedinto a partition member '58 fitted into a recessformed in the upperportion of the casing section Il, said valve ring 'l1 being held inposition by bolts 19; the partition member 'i8 is fixed in place in theaforesaid recess, by means of a hood 80 mounted upon the aforesaid upperportion of the casing section Il' and secured in place thereon by screwsor the like 3|; the interior of the hood 89 constitutes a compartment8|)ad which is separated from the outlet chamber |'!a by the partitionmember 'I8 and valve ring Tl, communication between the compartment imaand the outlet chamber ||a being controlled by the flap member 69 inco-operation with the valve seat '16. As shown in Fig. l of thedrawings, the outwardly directed passage 23a connects the main linechannel 2|a with the compartment 80B.

Thevalve ring 'I7 is threaded into the partition member I8 so as to beadjustable therein and to enable said valve ring 'H to be screwedupwardly against the flap member 69 so that a portionv of the vweight ofthe duplex valve may be carried by the valve ring 17 to thereby causethe fiap member 69 to firmly seat itself upon the valve seat 76 toinsure a tight closure of the valve. The hood 89 is preferably providedwith oneor more lifting handles 82 to facilitate the removal of saidhood 8G when this is required or advisable, said hood 80 further beingprovided with an air relief valve 93 of conventional type for permittingair to escape from the compartment 85 when water is first introducedinto the same.

As shown in Fig. 4, the outer ends of the bearpact of the flap members68 and 69 against the ings'12a whereby the support 12 is mounted on therod 13 are internally threaded for the reception of thrust-bearing caps84 and 85 which, by engagement with the opposite ends of the rod 13, fixthe duplex valve unit against lateral movement. A slender shaft 86 isdetachably connected with the thrust-bearing cap 85 and extendshorizontally in registry with the axis of the rod 13 through a suitablestufiing box 81 of the casing section |1 into an externally located gearbox 88. The shaft 86 at its outer end carries a bevel gear 99 whichmeshes with a co-operating bevel gear 96 fixed upon one end of ailexible shaft 9|, as-shown in Fig. 2; the flexible shaft 9| extendsinto the casing 48 of the totalizing means into connection With a cam 92journalled in teriorly of said casing 48 Aon bearing brackets 93. Itwill be noted with this arrangement that any pivotal movements oftheaforesaid duplex valve on the rod 13 will be transmitted through theflexible shaft 9| to the cam 92, the ratio of the bevel gears 89 and 96being preferably three to one so that angular movements of the cam arethree times as great as corresponding movements of the duplex valveabout the rod 13. The cam 92 co--operates with a roller 94 rotatablymounted in the lower forked end of the member 65, as shown in Fig. 6;'the purpose of this arrangement will appear more clearly from thedescrip` tion hereinafter.

To facilitate accurate seating of the flap members 68 and 69 0n theseats 24 and 16 respectively, particularly in cases in which the pivotrod 13 is not in accurate true alignment, the flap members 68 and 69are,v connected with the carrier 19 by means of ball and socket joints;the latter comprise recessed members 95 suitably mounted ron the carrier10 and opposed recess members 96, saiclrecess members 95 and 96 being inengagement with curved projections 91 form-` ing integralparts of theflap members 68 and 69.

The latter and the elements comprising the ballv and socket jointsaresecured in place upon the carrier 10 by bolts 98 and nuts 99 as clearlyshown in Fig. l. An additional advantage pro'- vided with the ball andsocket connections of the ilap members 68 and 69 with the carrier 19resides in the fact that said ball and socket connections permit the useof annular line"contact between the ilap members 68-69 and therespective seats 24r and 16` thereof and eliminating the customarysurface contact which often causes binding or sticking and prevents thevalve from opening under the desired difference in pressure between theinlet and outlet sides of the valve. In the illustrated example theaforesaid line contact is secured `by roundingthe valve seats 24 and 16as previously indicated. The line con tact referred to has the furtheradvantagethat it permits the use of a copper or other suitable metalwasher |60 on the flap members 68 and 69 for engagement with the seats24 and 16 instead of the soft rubberwash'er heretofore generallyemployed for thisptupose; in practice it hasbeen found that theVgenerally utilized soft rubber Washers swell unevenly during use andpermit unintentional leakage past the valve, which objection is entirelyavoided with the illustrated construction. With the latter in actualservice after the hinge or pivot bearings of the duplex valve becomeslightly worn, the flapl members 68 andr 69 are capable of automaticallyadjusting themselves by reason of the ball and socket connections withthecarrier 16 to always maintain a uniform and eiicient closure throughthe-imseats 24' and 16 when the valve'closes.

In practice the operation is as follows: When there is no flow throughthe meter the flap members 68 and 69 are seated against the seats 24 and16 by their own weight combined with that of the carrier 16 as indicatedby full lines in Fig. 1, and all parts of the meter are under the samepressure. It is assumed that the meter is set in a pipe line with asuitable control valve in the outlet pipe connected with the outlet 8 ofthe section Il, and that a flow 'of Water is started through the meterby the opening of this control valve which may be of any conventionalform and has not been illustrated; this flow of water `developed by theopening of the aforesaid valve through the meter will obviously bethrough the channels that offer the least resistance. As at this stagethe nap'members 66 and 69 of the duplex valve are in engagement with theseats 24 and 16 respectively, fiow of water through the main linechannel |5a, Zla, |19 will be prevented and the water at rst OWv/'illtherefore pass through the chamber 29, the port 3|`and by-pass channels22 to the outlet chamber I1a as indicated by the arrows in Fig. l.

Whenever the amount of water being used is such as to lbringy about apredetermined difference in the pressure conditions between the inletchamber l5a and the outlet chamber lifL of say, for instance, fourpounds to the square inch, the ap members 68 and 69 willbe lifted fromthe seats 24 and 16 and a portion of the totallow will be divertedthrough'the main line channel l5, Zia, |1, yand the outwardly directedchan nel 23a. The flow through the channelZSa is negligible, thischannel being intended merelyto transmit the pressure head from thechamber llia to .the compartment 8|)Ft but being sumeiently large toprevent clogging. Increase of cw through the meter` willv cause thecarrier 10 yto pivotally swing on the rod 13 through increasing angulardistances until thev full open position is reached as indicated bydotted lines in Fig. l.

As the valve opening increases, the proportion of total flow whichvpasses through the by-pass channels 22 decreases with the .result thatwith they valve in the full open position only a small percentage ofsaid total flow will pass through suchby-pass channels 22. With thevalvefull open the proportion of the total flow through the by-passchannels is determined by the ratio ofV the diameter of the throat-piece2| to the diameter of. the inlet chamber I5a and by thev size oftheby-pass channels 22; in the preferred construction the diameter ofthe inlet chamber l5a should preferably be at least twice the diameterof the throat-piece 2| so that an appreciable difference in pressurehead will obtain between said inlet chamber I6SL andthe outlet chamber|'la at the outlet ends 22a ofthe bypass chan nels 22. The arrangementof the ley-pass chanvnels 22 around the throat-piece 2i, and theterminating ends thereof at said throat-piece 2|, where the pressuredrop is greatest, insures a maximum hydraulic eiiciency and the diversion of a flow through the by-pass channels 22' suiiicient to actuatethe piston 36 when the flap members 68 and 69 are removed from theirrespective seats.

Because ordinary castings used in water meter construction are as a rulenot uniform, it is desirablev to make'the port 3| vand the by-passchannels 22 of liberal dimensions and to introduce a controllableobstruction to the flow such asis illustrated by the orifice plate 32illustratedv in Fig. l. By substituting plates 32 having openings ofdifferent dimensions, the pressure-head loss in the by-pass channels 22may be modied i, and a greater or lesser proportion of the total iiowdiverted through the by-pass channels 22 when the iiap members 58 and 69are away from their seats.

Owing to the fact that when the iiap members 68 and 59 ci the duplexvalve are seated upon the seats 2li and l@ respectively, the entire iiowthrough the meter must pass through the bypass channels 22 and that whensaid duplex valve is open, only a portion of such ow passes through saidoy-pass channels 2?., it is apparent, unless special provisions are madeas will appear hereinafter, that a single totalizer fixed in positionand geared to show a quantity of water passed through the meter when theentire iiow is through` the by-pass channels 22, would, when the duplexvalve is in its open position, register only a proportionate part of theflow passing through the by-pass channels 22. In order therefore thataccurate registration of all iiows through the meter may be obtained,two totalizers 54 and 55 such as shown in the illustrated example, areemployed. The one totalizer 54 is fixed in position and is geared toregister the total how through the meter when. the flap members 58 and55 are seated.` The other totalizer 55 is geared to register thedifference between the total flow, when the duplex valve is in the fullopen position. and the flow registered by the tctalizei' 5G. Theregistration of intermediate flows is accomplished by means of the cam92 which acts on the roller 513 in dependence upon the pivotal movementsof the duplex valve, and by moving the carriage 65 on the rods 6i shiftsthe friction wheel 5I across the face of the disc lf2 in such mannerthat the sum of the readings of the totalizers 513 and 55 indicates thetotal flow through the meter. As shown in Fig. 6, when the duplex valveis seated, the friction wheel 5i is located at the center of the disc 45and is held in this position by means of springs 61a and the roller 9Gwhich bears against the periphery of the cam 92. friction wheel 5l islocated at the center of the disc 44, the motion of the latter will notb e transmitted to the totalizer 55 but for anygiven rotative speed ofsaid disc 54 the farther away from the center of the disc that thefriction wheel 5i is shifted, the greater will be the speed of thecounter gears and the greater will be the indication of the totalizer55, so that any desired percentage registration of total ow can beobtained by providing the cam 32 with suitable outline.

Fig. 8 shows typical curves for a meter constructed in accordance withthe principles of the instant invention. In the diagram illustrated inthis ligure the curves A and B show the percentage of the total flowregistered by the tota-lizer 54; For all rates of ow up to the point E,

,. when the duplex valve begins to open, the entire new through themeter is registered by said totalizez` 5d. From the point E to the pointF which is the point at which the duplex valve reaches its fully openposition, the totalizer 5d registers decreasing percentages of the totalflow and from the point F to the capacity of the meter said totalizer 5dregisters uniformly a given small percentage of said total flow. Theordinate D in the diagram of Fig. 8 represents the percentage of thetotal flow registered by the total- Obviously, when theizer 55 betweenthe-points E and F, the varying percentages being obtained by the actionof the cam 92 which causes the friction wheel 5l to be moved across theface of the disc Ml. For all rates of flow from the point F to thecapacity of the meter the totalizer 55 registers the uniform percentagedifference between the total ow and the ow registered by the totalizer54. It will be seen that for any given rate of ow through the meter, thesum of the readings of the two totalizers 54 and 55 will give the totaliiow through the meter as represented by the curves A and C in Fig. 8.

In order that the principles which govern the automatic functioning ofthe duplex valve of the illustrated meter may be better understood, thefollowing description is added:

When thereA is no i'low through the meter, the duplex valve is seated byits own weight whichA is divided between the two Valve seats 24 and 16.The forces acting on the duplex valve and tending to swing it about thehorizontal rod 13 are the forces resulting from the differentintensities of water pressure acting on the flap members 68 and 69. Whenthe duplex valve is seated, the intensity of the pressure acting on theinlet side of the flap member 68 is the same as the intensity ofpressure in the chamber l5il and the total pressure acting on the duplexvalve is the intensity of pressure multiplied by the area within thevalve contact-circle. The eiect of the total pressure is the same as asingle force applied at the center of the flap member 68 acting in ahorizontal counter-clockwise direction and tending to open the duplexvalve b y swinging it on its pivot or hinge. The intensity of pressureacting on the outlet side of the flap member 68 is the same as theintensity of pressure in the chamber Ha, and the total pressure actingon the outlet side of the valve is the intensity of pressure in thechamber l 1 multiplied by they area within the valve contact-circle. Theeffect of this total pressure is the same as a single force applied atthe center of the flap member 68 acting in a horizontal clockwisedirection and tending to close the valve by turning it on its pivot orhinge. When there is no iiow through the meter, the intensity ofpressure in the chamber 15a, which acts on the inlet side of the flapmember 68, is the same as the intensity of pressure in chamber il, whichacts on the outlet side of said member 68, and consequently the force onthe inlet side on the ilap member 68' corresponds to the force on theoutlet side thereof, which two forces being equal and opposite indirection therefore neutralize each other. This is due to the fact thatthe surface areas on opposite faces of the ap member 68 areapproximately equal, because the engagement of the ilap member 68 withthe valve seat 24 is in the nature oi a line contact, the valve seat 24being rounded or otherwise formed to attain this result. As water passesthrough the by-pass channels 22, because of the opening of a controlvalve on the outlet side of the meter, resistance is producedr by uidfriction and an amount of head is used up that'is proportional to thevelocity of the flow. Consequently, the intensity of the pressure in thechamber l'lEL becomes less than the intensity of pressure in the chamberl5a and the two opposing forces acting on the ap member 68 are thereforeunequal. The difference between the two forces or in vother words theresultant force acts in a counter-clockwise direction and tends to openthe duplex.valve..'1his resultant force may be determined by multiplyingthe differencey between the pressures in' lia .and |18, or differentialpressure by thearea within the contact circle. The .moment of theresultant force with respect to the center of the hinge or rod 13 is theproduct of the magnitude of the force and the perpendicular distance orlever-arm bey made less than the moment of the horizontal force.A

lThe weight of the valve has substantially the sainev effect in tendingto close it as a single vertical force` equal to the combined weight ofthe iiap members 68 and 69 and the carrier 10 passing through the centerof gravity of the mass, and the moment of this force with respect tothecenter o f the hinge is the product of the magnitude of the iforcev andthe perpendicular distance between the force and the center of -thehinge.

It is apparent from the foregoing that the horizontal force acting onthe duplex valve tendingy to `open it is opposed by the two verticalforces tending to close it. The relation between 'the several forcesacting on the valve may be expressed by the formula:

- PALa=PBLblWLw l In which:

P=vdiierence between pressure in chamber Ia and 11a, or the differentialpressure;

A=area within vertical valve-seat ring; La=lever` arm a, orperpendicular distance between horizontal line through center ofvertical flap `an'd center of Valve-hinge;

diameter, and a vertical valve-seat-ring which is 12.5 inches indiameter, would be as follows: P=4 lbs. to the lsquare inch.

A: 122.7 square inches. `I.a' -.'12.t' inches.

B: 1.17.4 square inches. 'Lire 11.5 inches.

W=80 pounds (computed) Lw- ,-9.19'inches (computed). j 4X122.7 12.5=-`4'117.4X 11.5-l-80X 9.19

, u. e135,=54oo+735=6135. A valve having the dimensions and weightvgiven above would remain seated until the differential pressure reachedfour pounds to the square inch v'vhen all of the forces mentioned aboveacting onzthe valve would be balanced and a slight increase indiierential pressure would move the valve from its seats.

With the opening of the valve a new force, resulting from the stream ofwater iiowing through the main line channel and impinging on the inletside of the vertical flap, is added. This force increases with the flowand swings the valve to the full open position as in ordinary singleflap check valves.

It will be seen from the foregoing numerical example that in a check.valve with a single vertical ap a force equal to the area A of the iiapmultiplied by the differential pressure P, which equals 490.8 pounds,would be required to hold the valve against its seat until the requireddifferential pressure was produced. With lever arms La and Lw of say'12.5 inches, a weight of 490.8 lbs. would be required. In valvesheretofore constructed this force was obtained by means of'counterweights, heavy spiral springs, or exposure of a portion of thevalve seat areato atmospheric pressure. .t

In the form of the meter shown in Fig. 7, the i inlet section I5 of themeter casing and the elements associated therewith are substantially thef same as those illustrated in Fig. 1, and require no furtherdescription. In' this form, however, the outlet section I'l'b4 of themeter casing is oonstructed with an arched portion Slb curved in an archaving the pivot I3a as a center, said pivot l-3a corresponding to therod 13 of the form illustrated in Fig. 1. The interior of thefarchedportion 801 constitutes a compartment 8B corre-I sponding to thecompartment 8G@ of Fig. 1 and communicating with the interior of athroatpiece 2 lb by means of an outwardly directed passage 23b, it beingunderstood that the throatpiece 2|b is provided with by-pass channels221 corresponding to the llay-pass channels 22 orv Fig. l and likewiseestablishing communication between the passage 23 of the section I5 andthe outlet chamber 11 of the section Hb. The one end of the throat-piece2 Ib is formed with a valve seat 211a corresponding to the valve seat 24of liig.v v l 68a similar to the flap member 68 and likewise formingpart of a duplex valve in the form of the` meter under discussion, whichduplex `valve is mounted to swing about the pivot 13a which may comprisea rod similar to the rod 13 of the form first described. The duplexvalve further includes a second flap member 69a corresponding a flangeportion screw-threaded into the arched portion 8|]b so as to beadjustable therein vrelatively to said ap member 69a.` In the form nowbeing described, the flap member 69a controls the communication betweenthe compartment 'Silo and a compartment Hd formed in an extension |1projecting upwardly from the section Hb andv closed at its upper end bya hood Bild similar to the hood 8B and xed upon the extension He in anyconvenient manner as by means of bolts Bla.

The operation of the form of meter illustrated in Fig. 7 issubstantially the same as the one previously described and will beapparent from the description hereinbefore.

In operation, when the flow through the meter is just sucient to createthe required differential pressure to start the valve in motion, saidvalve opens suddenly and assumes a position in which the oblique face ofthe washer 68h is in approximate alignment with the outlet end of thethroatpiece 2lb; a similar operation is effected in the flap member G9awhich is made of slightly less diameter than the inner diameter of thescrewthreaded iiange portion of the valve ring 17a, as shown in Fig. 7.

The weight of the valve is not just suiiicient to close it when the flowis reduced or stopped, and since, when the valve swings from its seatsthe moments about the pivot '13a are substantially the same for anyposition of *he valve, only a slight force resulting from impingement ofthe flowing water through the main line channel, is required to swingthe valve to the fully open position.

In this form of valve, the parts should be so proportioned that thei'iow through the by-pass channels 22b or their equivalent will be largeenough under a four pound pressure drop between the inlet chamber la andthe outlet chamber HC in Fig. 7 or the equivalent chambers in Fig. l, atthe outlets of the bynass channels 22b in Fig. 7, or 22 in Fig. l, toproduce suiiicient low through said by-pass channels to actuate themeter.

From the foregoing description it is clear that the novel features setforth enable a meter of the fire-service type to be constructed in whicha single measuring piston serves to accurately measure all flows passingthrough the particular meter in question; it is further apparent thatthe construction of the meter is simple and durable and extremelyeiiicient and accurate in action. It will be understood that while theduplex valve in its various forms as shown herein is particularlyadapted for use in water meters, it is not limited to such use and maybe readily adapted for other purposes.

The novel water meter possessing the characteristics set forth herein isparticularly suitable for measuring the supply oi water where only onesupply line is provided for 'both fire protection and industrial use,and further is suitable for use as a master meter for measuring thetotal supply of water delivered to a town or other water district. Whenthus used the meter overcomes measurement inaccuracies in existing typesof meters occurring in such meters, particularly at that point at whichthe valve begins to open and permitting some water to ow through themeter Without registration; the novel meter avoids this possibility andguarantees accurate measurements under all conditions, particularly incases where the water is used for prolonged periods at rates where thevalve begins to initially open.

Various changes in the specific forms shown and described may be madewithin the scope of the claims without departing from the spirit of theinvention.

I claim:

I. In a water meter, the combination of a casing having an internal mainline channel provided with an independent compartment communicating withsaid constricted portion and the outlet side of said main line channel,a valve `seat at one end of said constricted portion, a sec- -ond Valveseat between said compartment and said outlet side of said main linechannel, and a duplex valve consisting of'a carrier pivotally mounted insaid casing, and valve flap members of predetermined differential areasmounted on said carrier and co-operating with said seats to control theflow through said meter, the valve flap member co-operating with saidsecond valve seat being-iniluenced by pressure enective in said'independent compartment through its communication with said constrictedportion of the main line channel to maintain both valve flap members inthe closed position until a predetermined pressure diierential isdeveloped between the outlet and inlet sides of the meter.

2. In a water meter, the combination of a casing having an internal mainline channel including a constricted intermediate portion and includinga by-pass channel establishing communication between the inlet andoutlet sides of said main channel, said casing further being providedwith an independent compartment communicating with said constrictedportion and the outlet side of said main line channel, a pair ofcooperating'valve seats in transverse relation to each other and locatedrespectively at one end of said constricted portion and between saidcompartment and the outlet side of said main line channel, and a duplexvalve consisting of a pivoted carrier having its supporting pivotbetween said valve seats, and cooperating valve iiap members ofpredetermined differential areas on said carrier in transverse relationto each other for co-operation with the respective valve seats tocontrol the ilow through said meter,

the valve flap member co-operating with the valve seat between saidcompartment and the outlet side of said main line channel beinginfluenced by pressure effective in said independent compartment throughits communication with said constricted portion of the main line chan-L.'

nel to maintain both valve flap members in the closed position until apredetermined pressure differential is developed between the outlet andinlet sides of the meter through said by-pass channel.

3. In a water meter, the combination of a casing having an internal mainline channel including a constricted intermediate portion and includinga by-pass channel establishing communication between the inlet andoutlet sides of said main channel, said casing further being providedwith an independent compartment communicating with said constrictedportion and the outlet side of said main line channel, a pair ofsuperposed Valve seats facing in opposite directions and locatedrespectively at one end of said constricted portion and between saidcompartment and the outlet side of said main line channel, and a duplexvalve consisting of a pivoted carrier having its supporting pivotbetween said valve seats, and valve ap members of predetermineddifferential areas on said carrier in a substantially common plane forco-operation with the respective valve seats to control the flow throughsaid meter, the valve flap member cooperating with the valve seatbetween said compartment and the outlet `side of said main line channelbeing influenced by pressure effective in said independent compartmentthrough its including a constricted intermediate portion andCOmmllnCal'fOll'Wh-Sad constricted DOItOn 0f the main line channel tomaintain both valve flap members in the closed position until a pre1determined pressure differential is developed between the outlet andinlet sides of the meter through said by-pass channel.

4. In a water meter, the combination of a casing having an internal mainline channel including avconstricted intermediate portion and providedwith an independent compartment communicating with ,said constrictedportion and the outlet side of said main line channel, a Valve seat atone end of said constrictedportion, a second valve seat between saidcompartment and said outlet side of said main line channeLvand a duplexvalve consistingv of a carrier pivotally mounted in said casing, valveflap members of predetermined diiierential areas adapted to cooperateWith said seats to control the ilow through said meter, and ball andsocket connections between said carrier and said valve rflap .memberswhereby the latter automatically vadjust themselves independently ofeach other to fit against therespective seats, the valve lflap member(zo-operating with the second valve seat being influenced by pressure insaid independent compartment through its communication with saidconstrcted portion of the main line channel to maintain both valve flapmembers in the rbranch connection between the inlet and outlet sides ofsaid main line channel, and a continuously open by-pass channel betweensaid inlet and outlet, a pair of valve seats in said casing locatedrespectively in said main line channel and said branch connection, and aduplex nap valve consisting of a carrier pivotally mounted in saidcasing, and a pair'of flap valve members both mounted on said` carrierto move therewith and co-operating respectively with the respectivevalve seats to control the ilow through said main `line channel 'andsaid branch connection to the outlet side of the meter, the valve flapmember co-operating with the valve seat in said branch connection beinginfluenced'by pressure in the v,

latter to maintainboth valve ap members in the closed position untilapredetermined pressure differential is developed between the outlet andinlet sides of the meter through said by-pass channel. 'A

` EDWARD NUEBLING.

